1. Field of Invention
The present disclosure relates in general to an elevator for an oilfield tubular. More specifically, the present disclosure relates to an elevator having a locking system for maintaining engagement of the elevator with a tubular when the elevator encounters a collar on the tubular.
2. Description of Prior Art
Tubing elevators typically include left and right bodies that couple together on one end with a barrel type hinge. A semi-circular recess is generally provided axially along an inner surface of each of the bodies. Closing the elevator brings the bodies together so their respective recesses face one another and engage opposing sides of a tubing string. Generally, a retainer and lug are provided for latching together the left and right bodies when in the closed position. Typically, the lug projects outward from a front surface of the right body and the retainer pivotingly attaches to a front surface of the left body; the retainer is positioned so that it can selectively swing into latching engagement with the lug. When the retainer swings into the latching position, the lug inserts into an opening formed through the retainer.
Tubing elevators usually are equipped with tie bars that mount on lateral sides of the left and right bodies. The tie bars are engaged by elevator links provided on a traveling block for raising and lowering the tubing elevator; where drilling rig drawworks are typically included for controlling movement of the traveling block. The left and right bodies are kept in the closed position as long as the retainer is adjacent the front surface of the right body and the lug is inserted into the retainer opening.